Showing papers by "Japan Atomic Energy Research Institute published in 2010"
TL;DR: The JT-60SA is a fusion experiment designed to contribute to the early realization of fusion energy, by providing support to the operation of ITER, by addressing key physics issues for ITER and DEMO and by investigating how best to optimize the next fusion power plants that will be built after ITER as discussed by the authors.
Abstract: The JT-60SA is a fusion experiment designed to contribute to the early realization of fusion energy, by providing support to the operation of ITER, by addressing key physics issues for ITER and DEMO and by investigating how best to optimize the operation of the next fusion power plants that will be built after ITER. It is a combined project of the JA-EU Satellite Tokamak Program under the Broader Approach (BA) Program and JAEA's Program for National Use, and it is to be built in Naka, Japan, using the infrastructure of the existing JT-60U experiment. This paper describes in detail the design of the JT-60SA Toroidal Field magnet and shows the strong points of each foreseen solution. Additional information about manufacturing procedures is given and technological issues are reported and critically analysed.
53 citations
TL;DR: In this article, the authors considered the heating mix of ITER for the two main scenarios and concluded that the present heating mix is appropriate. And they provided the necessary actuators to induce in a flexible way the best possible scenarios.
Abstract: This paper considers the heating mix of ITER for the two main scenarios. Presently, 73 MW of absorbed power are foreseen in the mix 20/33/20 for ECH, NBI and ICH. Given a sufficient edge stability, Q = 10-the goal of scenario 2-can be reached with 40MW power irrespective of the heating method but depends sensitively inter alia on the H-mode pedestal temperature, the density profile shape and on the characteristics of impurity transport. ICH preferentially heats the ions and would contribute specifically with Delta Q 0.5, and strong off-axis current drive (CD). The findings presented here are based on revised CD efficiencies gamma for ECCD and a detailed benchmark of several CD codes. With ECCD alone, the goals of scenario 4 can hardly be reached. Efficient off-axis CD is only possible with NBI. With beams, inductive discharges with f(ni) > 0.8 can be maintained for 3000 s. The conclusion of this study is that the present heating mix of ITER is appropriate. It provides the necessary actuators to induce in a flexible way the best possible scenarios. The development risks of NBI at 1 MeV can be reduced by operation at 0.85 MeV.
50 citations
TL;DR: In this paper, a very high temperature gas-cooled reactor (HTGR) and carbon free hydrogen production process (IS process) were developed to resolve energy security and global warming issues.
49 citations
TL;DR: In this article, X-ray diffraction and absorption was used to show that LaFe0.57Co0.38Pd0.05O3, one of the perovskite-based catalysts investigated for catalytic converter applications since the early 1970s, retains its high metal dispersion owing to structural responses to the fluctuations in exhaust-gas composition that occur in state-of-the-art petrol engines.
Abstract: Catalytic converters are widely used to reduce the amounts of nitrogen oxides, carbon monoxide and unburned hydrocarbons in automotive emissions. The catalysts are finely divided precious-metal particles dispersed on a solid support. During vehicle use, the converter is exposed to heat, which causes the metal particles to agglomerate and grow, and their overall surface area to decrease. As a result, catalyst activity deteriorates. The problem has been exacerbated in recent years by the trend to install catalytic converters closer to the engine, which ensures immediate activation of the catalyst on engine start-up, but also places demanding requirements on the catalyst's heat resistance. Conventional catalyst systems thus incorporate a sufficient excess of precious metal to guarantee continuous catalytic activity for vehicle use over 50,000 miles (80,000 km). Here we use X-ray diffraction and absorption to show that LaFe0.57Co0.38Pd0.05O3, one of the perovskite-based catalysts investigated1,2,3,4 for catalytic converter applications since the early 1970s, retains its high metal dispersion owing to structural responses to the fluctuations in exhaust-gas composition that occur in state-of-the-art petrol engines5. We find that as the catalyst is cycled between oxidative and reductive atmospheres typically encountered in exhaust gas, palladium (Pd) reversibly moves into and out of the perovskite lattice. This movement appears to suppress the growth of metallic Pd particles, and hence explains the retention of high catalyst activity during long-term use and ageing.
43 citations
TL;DR: In this article, a series of vortex images obtained in a disk with a pinning site reveals a unique line symmetry in vortex configurations, resulting in modifications of the shell filling rule and the magic number.
Abstract: Direct observation of vortices by the scanning superconducting quantum interference device microscopy was made on large mesoscopic disks of an amorphous MoGe thin film. Owing to the weak pinning nature of the amorphous film, vortices are able to form geometry induced, (quasi-)symmetric configurations of polygons, and concentric shells in the large disks. Systematic measurements made on selected disks allow us to trace not only how the vortex pattern evolves with magnetic field, but also how the vortex polygons change in size and rotate with respect to the disk center. The results are in good agreement with theoretical considerations for mesoscopic disks with sufficiently large diameter. A series of vortex images obtained in a disk with a pinning site reveals a unique line symmetry in vortex configurations, resulting in modifications of the shell filling rule and the magic number.
37 citations
TL;DR: In this article, the susceptibility of as-synthesized polymers to degradation upon their exposure to γ-ray radiation was investigated, and the size exclusion chromatographic results showed that chitosan and N-SC products in their dilute aqueous solution state were more subservient to degradation than in their solid film state, despite the much less exposure to the radiation.
32 citations
TL;DR: In this paper, the redox behavior of Ce(IV)/Ce(III, which is a surrogate for An(IV/An(III) (An=actinides), in a solution of nitrilotriacetic acid (NTA) at 25 C was investigated.
Abstract: Using cyclic voltammetry, we investigated the redox behavior of Ce(IV)/Ce(III), which is a surrogate for An(IV)/An(III) (An=actinides), in a solution of nitrilotriacetic acid (NTA) at 25 C. The cyclic voltammogram of Ce in a 0.1 M NTA solution at pH 6 showed a reversible one-electron redox reaction for Ce(IV)/Ce(III) at 0.51 V vs. Ag/AgCl. This redox potential was much lower than that obtained in 1 M nitric acid, indicating that Ce(IV) was preferentially stabilized by complexation with NTA. The redox potential in the NTA solution was independent of the Ce concentration from 2 to 20 mM, NTA concentration from 5 to 200 mM and pH between 3 and 7. These results indicated that no polymerization and no additional coordination of NTA and OH{sup -} to the Ce(III)-NTA complex took place during the redox reaction. As the speciation calculation of Ce(III) in the NTA solution showed that the predominant species was Ce{sup III}(nta){sub 2}{sup 3-} (H{sub 3}nta = NTA), the redox reaction of the Ce-NTA complex was expressed by the following: Ce{sup IV}(nta){sub 2}{sup 2-} +e{sup -} Ce{sup III}(nta){sub 2}{sup 3-}. The logarithm of the stability constant of Ce{sup IV}(nta){sub 2}{sup 2-} was calculated to be 38.6 {+-} 0.8 for Imore » = 0 from the redox potential shift of Ce(IV)/Ce(III) in the NTA solution. The value was in good accordance with the stability constant of the Np{sup IV}(nta){sub 2}{sup 2-} complex, demonstrating that the aqueous coordination chemistry of Ce(IV) with NTA is quite similar to that of An(IV). These results strongly suggest that a negative shift of the Pu(IV)/Pu(III) redox potential in the NTA solution should make Pu(IV) more stable than Pu(III) even in a reducing environment.« less
18 citations
TL;DR: The results suggest that Pb 2+ more weakly inhibits the growth of S. cerevisiae than UO 2+ 2 , and produces different stresses in S. Cerevisiae compared to UO2+ 2, where Pb had accumulated inside the cells.
Abstract: We have examined the responses of Saccharomyces cerevisiae in media containing Pb 2+ ions and compared it to those in media containing UO 2+ 2 ions to elucidate the stress effects of heavy elements. Cultivation of S. cerevisiae in a medium containing 1.0 × 10 −4 M Pb showed nearly the same growth as that in the control medium while growth was inhibited in the medium containing 1.0 × 10 −3 M Pb. Backscattering electron image analyses of thin sections of cells showed that Pb had accumulated inside the cells. These results were different from those for UO 2+ 2 ions obtained in the previous study, where 1.0 × 10 −4 M U inhibited the growth of S. cerevisiae, and UO 2+ 2 ions were sorbed on the cell surface. Two-dimensional (2D) gel electrophoresis analysis of the proteins extracted from the S. cerevisiae exposed to Pb 2+ ions showed that several specific protein spots were expressed after cultivation with Pb, that did not appear in the control medium. The isoelectric point in the gel strip and molecular sizes ...
14 citations
TL;DR: In this paper, an assessment of a creep-fatigue crack initiation and growth for a Mod. 9Cr-1Mo steel structure with weldments has been carried out based on an extended French RCC-MR A16 procedure.
Abstract: An assessment of a creep-fatigue crack initiation and growth for a Mod. 9Cr-1Mo steel structure with weldments has been carried out based on an extended French RCC-MR A16 procedure. The A16 defect assessment guide provides assessment procedures for a creep-fatigue crack initiation and growth for an austenitic stainless steel, but no guidelines are available yet for a Mod. 9Cr-1Mo steel. A creep-fatigue structural test was carried out for a Mod. 9Cr-1Mo specimen with two hours of a hold time at 873 K and various primary nominal stresses. σd approach was employed to evaluate a creep-fatigue crack initiation, and an assessment of a creep-fatigue crack growth at a defect has also been carried out. The evaluation results were compared with the observed images from the structural test.
13 citations
TL;DR: In this article, it was shown that the lattice specific heat is due to the hindered rotation of interstitial molecules in the periodic potential of a graphite neutron-irradiated graphite this article.
Abstract: Irradiation-induced increase in the low-temperature specific heat has been measured in the temperature range of 19\char21{}43 K in graphite neutron-irradiated to $14\ifmmode\times\else\texttimes\fi{}{10}^{20}\text{ }\text{n}/{\text{cm}}^{2}$ $(Eg1\text{ }\text{MeV})$ around 333 K The increase of the lattice specific heat is interpreted as due to the hindered rotation of interstitial ${\text{C}}_{2}$ molecules in the periodic potential of $V(\ensuremath{\varphi})=({V}_{0}/2)(1+\text{cos}\text{ }2\ensuremath{\varphi})$, where $\ensuremath{\varphi}$ is the angle of rotation and ${V}_{0}$ is 0040 eV The first-excited rotational level is 00058 eV above the ground state and the rotational frequency is $139\ifmmode\times\else\texttimes\fi{}{10}^{12}\text{ }{\text{s}}^{\ensuremath{-}1}$ This result shows that ${\text{C}}_{2}$ molecules do not form covalent bonds with atoms in the surrounding graphite layers It is in marked contrast with the result of recent first-principles theoretical calculations that interstitial atoms form strong covalent bonds with atoms in the graphite layers The concentration of ${\text{C}}_{2}$ molecules is estimated to be $f=116%$ The hole concentration, deduced from the electronic specific heat and the SWMcC band model, suggests that one single vacancy creates one hole and the single vacancy concentration is $2f$ Since the measurement of the lattice specific heat gave the concentration of the defects directly, we could evaluate some physical properties for a unit concentration of the defects The volume changes by a single interstitial atom, an interstitial ${\text{C}}_{2}$ molecule, and a single vacancy are deduced to be $26\ifmmode\pm\else\textpm\fi{}03$, $93\ifmmode\pm\else\textpm\fi{}14$, and $\ensuremath{-}046\ifmmode\pm\else\textpm\fi{}007$ atomic volumes, respectively The formation energy of a Frenkel pair is estimated to be $126\ifmmode\pm\else\textpm\fi{}25\text{ }\text{eV}$ The phonon scattering with a reciprocal relaxation time proportional to ${\ensuremath{\omega}}^{15}$, where $\ensuremath{\omega}$ is the angular frequency of phonons, is attributed to the scattering of phonons by the disklike strain around interstitial ${\text{C}}_{2}$ molecule clusters A broad dip in the $a$-axis thermal conductivity observed below room temperature is attributed to the resonance scattering of phonons by the hindered rotation of interstitial ${\text{C}}_{2}$ molecules as well as by the vibration of these molecules as rigid units The positron lifetime of 350 ps is suggested to be the lifetime of positrons trapped in an open space on the periphery of the interstitial clusters of ${\text{C}}_{2}$ molecules The well-known Wigner energy is stored mainly as interstitial ${\text{C}}_{2}$ molecules and single vacancies
12 citations
Patent•
23 Aug 2010TL;DR: In this article, a method of forming a zirconium-loaded fibrous adsorbent material having phosphoryl groups was proposed, which includes grafting a reactive monomer having the same groups onto a polymeric substrate and loading ZIRconium such that the material has 4.0 or 4.2 mmol/g.
Abstract: A method of forming a zirconium-loaded fibrous adsorbent material having phosphoryl groups, the method including: grafting a reactive monomer having phosphoryl groups onto a polymeric substrate; and loading zirconium such that the zirconium-loaded fibrous adsorbent material has a zirconium content in an amount of 4.0 or 4.2 mmol/g.
TL;DR: In this article, a linear forcing scheme was proposed to solve the Navier-Stokes equations for turbulent flows in real space. But the results of the linear forcing were not analyzed for the Lattice Boltzmann method.
Abstract: The Lattice Boltzmann Method (LBM) has proved to be a promising approach to solve the Navier–Stokes equations, especially for incompressible and isothermal cases. For turbulent flows, the quality of the predictions has been previously studied considering standard spectral forced (ten Cate et al., Comput Fluids 35:1239–1251, 2006) statistically homogeneous isotropic turbulence. In the present contribution, a recently proposed linear forcing scheme working in physical space (Lundgren 2003; Rosales and Meneveau, Phys Fluids 17(9):095106–1,8, 2005) has been integrated in a three-dimensional fifteen-velocity LBM formulation. Results have been analyzed, with special attention to the dynamics of the flow through the invariants of the velocity tensor. This topic had not been studied yet for the linear forcing, regardless of the nature (spectral or LBM) of the numerical method. Results fully agree with standard pseudo-spectral direct numerical simulations, results proving the validity of the LBM with linear forcing in real space to study this kind of turbulent flows.
TL;DR: In this article, the authors examined whether there are contributions to the shifts from deformation induced stacking faults to the presence of stacking faults for NiCrFe and 316 stainless steel alloys.
Abstract: Neutron diffraction measurements of strain in austenitic stainless steel alloys are presented to examine whether there are contributions to the shifts from deformation induced stacking faults. Differences between successive orders of reflections are consistent with the presence of stacking faults for 316 stainless steel but not for a NiCrFe steel.
Istituto Nazionale di Fisica Nucleare1, DSM2, University of Santiago de Compostela3, University of Łódź4, University of Ioannina5, Centre national de la recherche scientifique6, Vienna University of Technology7, Charles University in Prague8, Technical University of Madrid9, International Atomic Energy Agency10, CERN11, University of Coimbra12, Polytechnic University of Catalonia13, University of Notre Dame14, Spanish National Research Council15, Aristotle University of Thessaloniki16, Joint Institute for Nuclear Research17, Los Alamos National Laboratory18, Tokyo Institute of Technology19, Oak Ridge National Laboratory20, University of Seville21, University of Bologna22, Japan Atomic Energy Research Institute23, National Technical University of Athens24, University of Vienna25, Institute for Reference Materials and Measurements26, University of Basel27, ENEA28
TL;DR: A review of the most important results on capture and fission reactions obtained so far at n_TOF is presented, together with plans for new measurements related to nuclear industry.
Seoul National University1, Osaka University2, KEK3, Osaka Electro-Communication University4, Tohoku University5, Ewha Womans University6, Korea Research Institute of Standards and Science7, University of Tokyo8, Kyoto University9, Tokyo Institute of Technology10, Japan Atomic Energy Research Institute11
TL;DR: In this article, the decay widths Γ n and Γ p were determined in the exclusive coincidence measurement of the nucleon pairs in the back-to-back kinematics, and the branching ratio of the three-body process in the nonmesonic weak decay of 12ΛC was reported to be 0.29 ± 0.13 by reproducing the quenching of the nucleus yields.
TL;DR: In this paper, Iwata and Watanabe have addressed the issues raised by Latham et al. in their comment, and showed that self-interstitial atoms cannot form covalent bonds with atoms in adjacent graphite layers.
Abstract: In a recent paper [T. Iwata and M. Watanabe, Phys. Rev. B 81, 014105 (2010)], we have interpreted the irradiation-induced increase in the low-temperature specific heat of neutron-irradiated graphite as due to the hindered rotation of interstitial ${\text{C}}_{2}$ molecules with a rotational frequency of $1.39\ifmmode\times\else\texttimes\fi{}{10}^{12}\text{ }{\text{s}}^{\ensuremath{-}1}$ in the periodic potential with a height of 0.040 eV, and concluded that the ${\text{C}}_{2}$ molecules do not form covalent bonds with atoms in the adjacent graphite layers. In their Comment [preceding paper, C. D. Latham et al., Phys. Rev. B 82, 056101 (2010)] on this paper, based on the recent first-principles theoretical calculations and related experiments, Latham et al. assert that self-interstitial atoms cannot exist as clusters of nearly free ${\text{C}}_{2}$ molecules. In this Reply, based on the experiments, we address the issues raised by Latham et al. in their Comment.
01 Jan 2010
TL;DR: It is shown that B entrapped WOW emulsion would be applied to novel intra-arterial boron delivery carrier on BNCT to cancer, and, the possibility to apply BN CT to HCC is shown.
Abstract: Hepatocellular carcinoma (HCC) is one of the difficult to cure with combinational medical therapies. Tumour cell destruction in boron neutron capture therapy (BNCT) is due to the nuclear reaction between B atoms and thermal neutrons, so it is necessary to accumulate efficient B atoms to tumour cells for effective BNCT. We prepared BSH entrapped Water-in-oil-in-water(WOW) emulsion for selective intra-arterial infusion to HCC, and performed preliminary dosimetry with Japan Atomic Research Institute Computational Dosimetry System using CTscan imaging of HCC patient. The B concentrations in VX-2 tumour by WOW emulsion was superior to those by conventional emulsion. According to the rabbit model, the boron concentrations (ppm) of tumour, normal liver tissue, or blood is 61.7, 4.3, 0.1, respectively. In the epithermal lneutron dosimetry, the maximum tumour RBE dose, minimum tumour RBE dose, and mean tumour RBE dose are 43.1, 7.3, and 21.8 Gy-Eq, respectively, with the normal liver RBE restriction to 4.9 Gy, in 40 minutes irradiation. In this study, we showed that B entrapped WOW emulsion would be applied to novel intra-arterial boron delivery carrier on BNCT to cancer, and, we showed the possibility to apply BNCT to HCC.
TL;DR: In this article, the authors investigated the application of the area detector for the purpose of evaluating residual stress in rails by means of diffraction technique, and a rail used in the Hokuriku-Line of West Japan Railway Company (JR-West) was used as a specimen for this study.
Abstract: In this study, the authors investigated the application of the area detector for the purpose of evaluating residual stress in rails by means of diffraction technique. A rail used in the Hokuriku-Line of West Japan Railway Company (JR-West) was used as a specimen for this study. The rail was removed due to initiation of cracks caused by rolling contact fatigue. The present method refers to neutron stress measurement with a two-dimensional detector and corresponding data analysis.
TL;DR: In this paper, a finite element method was applied to estimate the initial stress state using stresses released after cutting a sample obtained by the X-ray method, and the results of FEM analysis and the Xray diffraction method confirmed that these methods can be used to evaluate the residual stress of the hoop direction.
Abstract: X-ray stress measurement is useful for determining, in a non-destructive manner, the surface stresses of engineered parts. However, the railway wheels cannot measure because this it is very large. So it should be measured using a scaled-down model. The problem is, however, how the stress release should be considered. In this analysis, the finite element method (FEM) was applied to estimate the initial stress state using stresses released after cutting a sample obtained by the X-ray method. Railway wheels were studied in this experiment. In the early 1990s, several railroads in the northeast of the U.S.A. experienced extensive cracking in the wheels of the commuter trains. Residual stresses in the hoop direction play an important role in mechanism fatigue damage. This paper will discuss about residual stress in the hoop direction in manufactured wheels. The results of FEM analysis and the X-ray diffraction method confirms that these methods can be used to evaluate the residual stress of the hoop direction. There is very good quantitative agreement between the simulated and measured stress distributions. It can be suggested that guessing guess stress release and the redistribution by the FEM analysis is possible. The residual hoop stress of the unused wheel presumed by this research has the residual stress of high compression in the wheel at the center of the rim up to 40mm depth. It is very safe because the residual stress state is compressive even when a crack occurs, and obstructs the crack’s progress. If a crack occurs by any chance, the stress state can obstruct the crack’s progress.
University of Santiago de Compostela1, Centre national de la recherche scientifique2, Istituto Nazionale di Fisica Nucleare3, DSM4, University of Łódź5, University of Ioannina6, Charles University in Prague7, Polytechnic University of Puerto Rico8, University of Padua9, University of Seville10, International Atomic Energy Agency11, CERN12, University of Coimbra13, University of Notre Dame14, Karlsruhe Institute of Technology15, Spanish National Research Council16, Aristotle University of Thessaloniki17, Joint Institute for Nuclear Research18, Los Alamos National Laboratory19, Tokyo Institute of Technology20, Oak Ridge National Laboratory21, Japan Atomic Energy Research Institute22, National Technical University of Athens23, University of Vienna24, Institute for Reference Materials and Measurements25, University of Basel26
TL;DR: In this paper, an Open Access article distributed under the terms of the Creative Commons Attribution-Noncommercial License 3.0, which permits unrestricted use, distribution, and reproduction in any non-commercial medium, provided the original work is properly cited.
Abstract: This is an Open Access article distributed under the terms of the Creative Commons Attribution-Noncommercial License 3.0, which permits unrestricted use, distribution, and reproduction in any noncommercial medium, provided the original work is properly cited
TL;DR: In this article, the deformation behavior of three austenitic stainless steels, JIS-SUS310S, 304 and 301L, were studied by static tensile tests and in situ neutron diffraction.
Abstract: Tensile deformation behaviors of three austenitic stainless steels, JIS-SUS310S, 304 and 301L, were studied by static tensile tests and in situ neutron diffraction. In the mechanical properties obtained by the static tensile tests, the 304 and 301L steels showed better balance of tensile strength and uniform elongation than the 310S one because of TRIP effect. The angular dispersion neutron diffractions with a wavelength of 0.16 or 0.182 nm were performed during stepwise tensile testing by using a neutron diffractometer for residual stress analysis (RESA) at the Japan Atomic Energy Agency. The lattice plane strain, stress-induced martensite volume fraction, dislocation density and so on were estimated by the profile analysis as a function of applied stress. The change in lattice plane spacing for austenite indicated four deformation stages. In the comparison of lattice plane strain among the tested steels, a phase stress caused by the stress-induced martensite seems to overlap the intergranular stress of austenite phase. Judging from the results of profile analysis, the strain partitioning of austenite phase in metastable austenitic steels became larger with increasing of the volume fraction of stress-induced martensite during tensile deformation.
Seoul National University1, Osaka University2, KEK3, Osaka Electro-Communication University4, Tohoku University5, Ewha Womans University6, Korea Research Institute of Standards and Science7, University of Tokyo8, Kyoto University9, Tokyo Institute of Technology10, Japan Atomic Energy Research Institute11
TL;DR: In this paper, the branching ratio of the three-body process in nonmesonic weak decay, 0.29±0.13, is determined taking account of the contribution of the 3 body process.
Abstract: The serious inconsistency problem between the values of experimental and theoretical n/ p ratio of the nonmesonic weak decay ofhypernuclei has been resolved recently. We have shown that the reason behind the problem was the quenching of the nucleon yields which in turn was due to the contribution of the three-body process. We have measured that the branching ratio of the three-body process in nonmesonic weak decay, 0.29±0.13, is so large that the absolute values of n and p must be determined taking account of the contribution of the 3-body process. In this paper, the recent studies toward the finding of the 3-body process via the exclusive coincidence experiments are presented.
TL;DR: In this paper, the magnetic torque of a high-quality PrFeAsO1−δ single crystal has been investigated at temperatures from 2 to 200 K in 1 and 5 T.
Abstract: The magnetic torque of a high-quality PrFeAsO1−δ single crystal has been investigated at temperatures from 2 to 200 K in 1 and 5 T. The superconducting anisotropy in PrFeAsO1−δ can well be approximated by the single-band Kogan torque theory. The superconducting anisotropy of PrFeAsO1−δ determined by analyzing the torque curve is weakly dependent upon changing temperature. The magnetism contribution to the torque from magnetic Pr ions becomes appreciable compared to the superconducting component. We argue that the Pr ions in the superconducting PrFeAsO1−δ single crystal show an antiferromagnetic spin ordering at 14 K. The spin structure thus reduced from the torque measurements is different from what neutron diffraction measurements predicted using polycrystalline specimen.
TL;DR: In this article, the authors present the In-NQR results under pressure (P ) in CeIr ( In 1 - x Cd x ) 5, where the occurrence of superconductivity (SC) is not related with the antiferromagnetic spin fluctuations (AFM-SFs) originating from the antifromagnetic quantum-critical point (CFM-QCP).
Abstract: We present the In-NQR results under pressure ( P ) in CeIr ( In 1 - x Cd x ) 5 . In CeCoIn 5 and CeRhIn 5 , the occurrence of superconductivity (SC) is related with the antiferromagnetic spin fluctuations (AFM-SFs) originating from the antiferromagnetic quantum-critical point (AFM-QCP). The high- T c SC ( T cmax > 2 K ) is realized in both compounds. However, in CeIrIn 5 which is apart from the AFM-QCP, SC occurs even without AFM-SFs and the quite small value of T cmax (∼1 K) is observed around P = 3 GPa . The mechanism of SC in CeIrIn 5 may be different from that in CeCoIn 5 and CeRhIn 5 .
TL;DR: In this paper, the leaching behavior of simulated high-level-waste glass in Japanese groundwater both on an in situ burial site and in a laboratory was reviewed. But the results of the experiments were limited.
Abstract: This paper reviews the leaching behavior of simulated high-level-waste glass in Japanese groundwater both on an in situ burial site and in our laboratory. During in situ burial leach tests, the glass is immersed in groundwater for up to 1 year and 7 months, retrieved, and analyzed. A leach rate obtained from the in situ burial tests is compared with other leach data under different conditions. Two factors, i.e., flow rate and composition of the groundwater, are extensively studied in the laboratory to supplement the in situ burial data. Effects of γ irradiation on the groundwater chemistry are also examined. Based on the results, mechanisms observed with the leaching of the glass in groundwater are discussed.
01 Mar 2010
TL;DR: In this article, the authors applied Mossbauer spectroscopy to 237Np in nitric acid solutions to study chemical states and found that Np(V) had 7 coordination number and Np (VI) had 8 coordination number from values of IS.
Abstract: We applied Mossbauer spectroscopy to 237Np in nitric acid solutions to study chemical states. Sample solutions were adjusted to 50 mg/ml of Np(V) and Np(VI) concentration in 0.6 M nitric acid solutions. These solutions were put into original designed containers for samples and mounted to sample holders. The values of isomer shift (IS, relative to NpAl2) of Np(V) and Np(VI) in 0.6 M nitric acid were −17.4(1) and −37.2(3) mm/s at about 10 K, respectively. It was found that Np(V) had 7 coordination number and Np(VI) had 8 in nitric acid solutions from values of IS.
TL;DR: In this article, the magnetic torque of superconducting PrFeAsO 1− δ single crystal using the torque magnetometer at temperatures from 2-K to 200-K in magnetic field of 30-kG was investigated.
Abstract: We investigated the magnetic torque of superconducting PrFeAsO 1− δ single crystal using the torque magnetometer at temperatures from 2 K to 200 K in magnetic field of 30 kG. The torque curve tends to have a singular shape compared to other superconductors. The analyses of the PrFeAsO 1− δ torque curves by the single-band and the multi-band Kogan model yield 3 γ λ γ ξ = 0.79 ± 0.01 and γ λ = 19 ± 3 in 30 kG at 20.5 K. The smallness of γ ξ (
TL;DR: In this article, an atomic model for the EUV sources is presented, which is useful both for theoretical investigation of the optimum conditions of the UEV sources and for the analysis of experimental spectrum.
Abstract: We show an atomic model of Sn for the EUV sources. We show an improvement of the model in terms of the
selection of energy levels and correction of the wavelength of the emission lines including resonance and satellite
lines of combined 4d-4f and 4p-4d transition arrays. Calculated spectrum agrees well with experiments, showing
that the present model is useful both for theoretical investigation of the optimum conditions the EUV sources,
and for the analysis of experimental spectrum. A modeling method to estimate the initial spatial profile of the
discharge path for the analysis of laser-assisted discharge pumped plasma sources is also proposed.
TL;DR: In this paper, two kinds of new techniques used were proposed to resolve the problem of unstable diffraction profile in the necessary direction and the edge effect which is generated by the overhang of the coarse crystal grains from the neutron irradiation area (gage volume).
Abstract: Internal stresses in aluminum casting alloy were measured by the neutron stress measurement method with the apparatus RESA in Japan Atomic Energy Agency (JAEA) In usual cases, coarse crystal grains are included in aluminum casting alloy These coarse crystal grains make it extremely difficult to estimate the internal stresses by the neutron diffraction [1] The two problems arise because of the existence of the coarse crystal grains The first problem is the production of an unstable diffraction profile in the necessary direction The second is the edge effect which is generated by the overhang of the coarse crystal grains from the neutron irradiation area (gage volume) In this study, two kinds of new techniques used were proposed to resolve these problems Firstly, the elastic theory based on the sin2ψ method is shown Diffraction peaks in several directions were found by use of the rocking curve method Following that, the lattice spaces in each principal direction were calculated from these diffraction peaks using the elastic theory Secondly, the distribution of edge effect around the gage volume was measured using a small bit of copper single crystal From this result, the edge effect was canceled out by the modified measurement method which was done symmetrically Finally, the aluminum casting sample which included coarse crystal grains was set to the tensile testing machine on RESA’s measurement table and the applicability of these new techniques were confirmed experimentally